| 摘要 |
Interference arrangements for testing wavefronts of coherent light beams are known which have a beam splitter, a plane reference surface and a prism. In order to construct such an arrangement so that it exhibits a high sensitivity with respect to the representation of an ideal wavefront starting as planar, the ideal state corresponding to optimum collimation, and in which, furthermore, there is the possibility to vary the sensitivity without a large technical outlay, the beam splitter is provided as the base face of the prism, which is arranged at a distance (H) which is between 5 mu m and 1 mm, and virtually parallel to the reference surface, the prism is adjusted with respect to the test light beams, which enter at one of its side faces and impinge at an angle of incidence onto the base surface at which they are partially reflected and through which they partially pass, the light beams passed being retroreflected at the reference surface into the prism and being brought into interference with the beams reflected at the prism base face, in such a way that the angle of incidence deviates slightly from the angle of total reflection, and the base face and the reference surface exhibit a deviation from planarity better than 1/5 of the wavelength of the test light beams referred to a distance of 5 centimetres in each direction.
|
